A “ship” means a high-tonnage vessel intended for maritime shipping, such as merchant shipping (oil tankers, container ships, fishing boats, etc.), warships (aircraft carriers, submarines, etc.) or alternatively large sailing boats or cruise liners. A ship's propeller typically takes the form of an assembly comprising an engine which drives the rotation of at least one propeller screw, this propeller being fixed to the hull of the ship, notably at the rear of the ship. In order to steer the ship, it is known practice to use what is known as a “pitch bearing” in order to orientate the propeller with respect to the hull of the ship.
A wind turbine generally comprises a nacelle, mounted for rotation on a mast and enclosing a generator intended to produce electrical energy, a rotor driven by the wind and provided with a hub supporting at least two blades, and a large-sized rolling bearing supporting the rotor.
In order to control the load supplied to the rotor, it is common to use a pitch bearing in order to orientate the blades of the wind turbine about their longitudinal axis according to the wind direction.
Such a rolling bearing comprises an outer ring fixed to the hub, an inner ring fixed to one of the blades and a plurality of rolling elements, such as balls, arranged between the inner and outer rings.
The rolling bearing comprises a ring gear provided with a peripheral inner gear teeth intended to mesh with an actuator via a gearwheel. It is known practice to form the internal gear teeth directly on the inner surface of the inner ring.
However, such a rolling bearing referred to as a pitch bearing works only when it is necessary to orientate the blade or the propeller and performs small rotations, such that only a small portion of the gear teeth is used. In addition, such a rolling bearing may be stationary for long periods of time, thus causing accelerated degradation.
As the gear teeth wears, it becomes necessary to dismantle the inner ring, or even the rolling bearing in its entirety, which is a relatively complex and expensive operation.
Reference may be made to document EP 2 474 735 which describes a device for mounting a blade pitch gear on a pitch bearing of a wind turbine comprising an inner ring, an outer ring and a gear which is fixed to the inner ring by a plurality of fixing means.
Although such a device allows only the gear to be changed in the event of wear, the plurality of fixing means generates great overall external dimensions and is complicated to achieve.
Reference may also be made to document U.S. Pat. No. 7,331,761 which describes a blade pitch bearing for a wind turbine comprising an inner ring, an outer ring and two rows of rolling elements which are arranged between the rings. The inner surface of the inner ring is provided with a plurality of teeth over a portion less than 200° and intended to mesh with a gear in order to orientate the blades of the wind turbine.
However, as the gear teeth wears, it then becomes necessary to remove the inner ring in its entirety.
It is therefore an object of the present invention to remedy these disadvantages.
More specifically, the present invention seeks to provide a rolling bearing that is easy to manufacture, to fit, is of small overall external dimensions, and allows the meshing means to be removed quickly and economically.